1. Field of the Invention
The present invention relates to a lock apparatus used in, for example, a glove box, which is axially supported to be rotatable, on an instrument panel of a vehicle.
2. Description of the Related Art
Although not specifically illustrated, JP-A-Hei. 4-60079 discloses a lock apparatus in which a pair of left and right link levers are supported axially to be rotatable, inside a housing provided by a glove box, thereby to fix a pair of slide pins, which go in and out at lock holes defined in the instrument panel, to an upper end portion of each of left and right link levers. A tension coil spring, which normally urges the respective left and right slide pins in directions of engaging into the lock holes, is mounted between lower end portions of the left and right link levers.
Further, in a state of closing the glove box, front end portions of the slide pins fixed to the upper end portions of the respective left and right link levers are engaged into the corresponding left and right lock holes on the instrument panel to lock the glove box at a closed position. In the case of opening the glove box by releasing the locked state, when respective projected arms provided to be opposed to middle portions of the pair of left and right link levers are pushed down against urge spring pressure of the tension coil spring by a swing operation of an operation handle, the respective left and right link levers are rotated in a direction reverse to the urging direction to retract the front end portions of the slide pins from the lock holes. Therefore, it becomes possible to move the glove box in an opening direction.
Although not specifically illustrated, U.S. Pat. No. 4,781,407 discloses another lock apparatus having the following configuration. A pair of inner cylindrical members formed cam grooves thereon is provided on the grove box main body movably. The respective inner cylindrical members are connected with a pair of slide pins going in and out lock holes defined in an instrument panel. A compression coil spring for urging the left and right slide pins normally in directions of engaging into the lock holes is mounted between the respective inner cylindrical members. On the other hand, on an operation handle, outer circular arc members being fitted to the inner cylindrical members to have the same axis and a pair of projected portions moving along groove edges of the cam grooves are provided.
Further, in a state of closing the glove box, front end portions of the slide pins are engaged into the left and right lock holes on the instrument panel to lock the glove box at the closed position since the projected portions on the operation handle are located on the inner sides of the corresponding cam grooves. In the case of opening the glove box by releasing the locked state, when the projected portions on the operation handle are shifted to outer sides of the cam grooves of the inner cylindrical member by operating to swing the operation handle, the left and right inner cylindrical members are moved in directions of approaching each other against urge pressure of the compression springs. Thereby, the front end portions of the respective slide pins are retracted from the lock holes. Therefore, it becomes possible to move the glove box in an opening direction thereby.
Further, JP-A-2003-13647 discloses still another lock apparatus hating the following configuration. A pair of outer cylindrical members formed cam grooves thereon are integrally provided on an operation handle. On the other hand, the inner cylindrical members having projected portions moving along groove edges of the cam grooves are fitted into the respective outer cylindrical members concentrically. The respective inner cylindrical members are connected with slide pins going in and out lock holes defined in an instrument panel. A compression coil spring for normally urging each slide pin in a direction of engaging with each lock hole is mounted in each outer cylindrical member.
In a state of closing the glove box main body, since the projected portions on the inner cylindrical members are positioned on outer sides of the cam grooves, front end portions of the left and right slide pins are engaged with the lock holes on the instrument panel to lock the glove box main body at a closed position thereof. In the case of opening the glove box main body by releasing the locked state, when the projected portions on the inner cylindrical members are moved to inner sides of the cam grooves of the outer cylindrical members by a swing operation of the operation handle, the left and right inner cylindrical members are moved in directions of being adjacent with each other against an urge spring pressure of the compression coil springs. Thereby, the front end portions of the respective slide pins are retracted from the lock holes. Therefore, it becomes possible to move the glove box main body in an opening direction.
Therefore, in the lock apparatus disclosed in JP-A-Hei. 4-60079, there is an advantage of simply achieving a locked state and a lock released state at both sides of the glove box, on the other hand. However, since the pair of left and right slide pins are fixed to the corresponding link levers, for example, when the glove box per se is destroyed, the slide pin cannot be easily removed from the link lever. Therefore, needless to say that it is impossible to reuse the slid pin. In addition, since it is impossible to detach the housing containing the link lever therein and the operation handle from the glove box due to this fact, it is also impossible to reuse them. Particularly, a cylinder lock is provided at a vicinity of the housing and the operation handle. Therefore, if the cylinder lock is reused, it is necessary to destroy the housing and the operation handle.
In the lock apparatus disclosed in U.S. Pat. No. 4,781,407 and JP-A-2003-13647, the front end portions of the slide pins can be retracted from the lock holes on the instrument panel by converting swing movement of the operation handle into linear movement. However, when an operator lets go the operation handle after bringing the glove box main body into the opened state under such a configuration, a constraining state between the projected portions and the cam grooves is released and the slide pins are projected in directions of the lock holes rapidly by receiving the urge spring pressure of the compression coil springs. Thereby, it is often feared to emit large impact sound because stoppers restricting a projection amount of the slide pins collide each other. Therefore, the operator is reminded of breakage of the lock apparatus to give an uneasy feeling, a distrustful feeling or an unpleasant feeling.
Further, such fear may occur when the slide pins are projected into the lock holes under closing the glove box main body in the opened state.